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One ring to rule the ball

One ring to rule the ball 3d printed Art Accessories The ball races freely around a loop, contained solidly within the single twisting wire.
The ball races freely around a loop, contained solidly within the single twisting wire.
  • Stainless Steel

    Bronze-infused stainless steel with visible print lines and rough feel.


If M.C. Escher had owned fidget toys, he would have worn "One ring to rule the ball" as a pendant. A single, continuous line contains a small ball that makes orbit after mesmerizing orbit but cannot escape, always held down in four directions. Available in solid, durable stainless steel with optional antique bronze and gold plated finishes to fit any context, "One ring to rule the ball" now also includes a free rubber necklace so that you can confuse your mind any time the fancy strikes you! One customer echoes many others in saying, "I couldn't put it down. This thing is just too fun!"

Purchases by those gracious customers have now paid for the design time on this piece so it is available on a pay-what-you-want basis. Ordering from this page contributes 5$ towards continuing work such as the new, even more impossible "One ring to pwn the ball" (just released October 18th!) which can be found at and the open-source "Ultimate Desk Toy" at . To download the original 3d file for your own use under a CC-BY license ( ) click "Download" at top right . To learn more about this design or other work from Terra Cotta, visit our website at


IN: 1.155 w x 1.155 d x 1.155 h
CM: 2.934 w x 1.102 d x 3.008 h


nice pun
March 11, 2014, 2:53 pm
Looks very good
June 9, 2013, 11:34 am
After refreshing the link "Download model" appeared. In the left bottom corner though.
June 6, 2012, 9:25 pm
Can't find the Download -button to get the 3d file.
June 6, 2012, 9:22 pm
@danilobuendia thanks for catching that--not sure why it was auto-added. @dannydrivethru this is certainly a strong enough design to have in your pocket, banging around with things (that's where I keep mine) but I'm not sure how you're going to get the keys on it! Maybe put a different keyring through the middle of it?
April 7, 2012, 10:32 pm
Hi, I'm new to this 3d printing stuff; just wondering would this be strong enough to use as a key ring, or would an average pocket put too much pressure on it? Thanks
March 27, 2012, 11:33 pm
This can be printed in Silver? I thought Silver doesn't allow moveable parts?
December 29, 2011, 8:33 am
Thank you, janiscortese -- you were the first to order it in glossy bronze (my own in that material has not yet arrived), so you are the only one to have seen "one ring" in that look worldwide! Pretty cool, hey?
August 24, 2010, 7:09 pm
Delightful thing, lovely in glossy bronze, pleased to hang it off my viola case. :-)
August 23, 2010, 7:57 pm
@semer I have added some photos to the forums at -- I hope they can give you a better idea of the design!
July 5, 2010, 8:24 am
Any chance of posting a picture of this "in action" worn as a pendant? I'm having a hard time with scale... yes, I know, the measurements are there... :) Anyhow very cool!
June 10, 2010, 12:33 am
Thank you, purchaser number 4! Model price reduced to $12.50, or two for $25
April 30, 2010, 11:05 pm
Only one more order and my first hour of design work on this piece will have been paid for--when that happens I will reduce the price to $12.50 (cost is $9.80). @pwnlrk I have new design out that I think you would like. Check it out at
April 11, 2010, 12:53 am
WOW, a double möbius skeleton. I love this piece! Well done!!
February 21, 2010, 4:50 am
Very nice and creative! Hope to see more soon ...
February 8, 2010, 3:41 pm
Wow that is mind boggling ! Wonderful design !
December 16, 2009, 11:56 pm